New evidence that all stars are born in pairs
Did our sun have a twin when it was born 4.5 billion years ago?
Did our sun have a twin when it was born 4.5 billion years ago?
Astronomy
Jun 14, 2017
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Researchers from Argonne's Environmental Science division participated in one of the largest collaborative atmospheric measurement campaigns in Antarctica in recent decades.
Earth Sciences
Dec 28, 2018
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A UK team of astronomers report the first detection of matter falling into a black hole at 30 percent of the speed of light, located in the centre of the billion-light year distant galaxy PG1211+143. The team, led by Professor ...
Astronomy
Sep 20, 2018
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While easily seen by people, the cotton-ball clouds (called shallow cumulus clouds) that drift overhead on partly cloudy days are hard for radars and many other instruments to observe and, therefore, hard to model and predict. ...
Earth Sciences
Jan 15, 2019
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An enormous comet—approximately 80 miles across, more than twice the width of Rhode Island—is heading our way at 22,000 miles per hour from the edge of the solar system. Fortunately, it will never get closer than 1 billion ...
Astronomy
Apr 12, 2022
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A team of researchers at the International Center for Relativistic Astrophysics has found evidence that suggests Sagittarius A* is not a massive black hole but is instead a mass of dark matter. In their paper published in ...
Astronomers using NASA's Hubble Space Telescope say they have crossed an important threshold in revealing a discrepancy between the two key techniques for measuring the universe's expansion rate. The recent study strengthens ...
Astronomy
Apr 25, 2019
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The outskirts of the Milky Way are home to the galaxy's oldest stars. But astronomers have spotted something unexpected in this celestial retirement community: a flock of young stars.
Astronomy
Jan 08, 2020
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A group of astronomers have shown that the fastest-moving stars in our galaxy - which are travelling so fast that they can escape the Milky Way - are in fact runaways from a much smaller galaxy in orbit around our own.
Astronomy
Jul 04, 2017
3
1271
Cloudy days are rare in the thin, dry atmosphere of Mars. Clouds are typically found at the planet's equator in the coldest time of year, when Mars is the farthest from the Sun in its oval-shaped orbit. But one full Martian ...
Planetary Sciences
May 28, 2021
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A cloud is a visible mass of droplets or frozen crystals suspended in the atmosphere above the surface of the Earth or another planetary body. A cloud is also a visible mass attracted by gravity, such as masses of material in space called interstellar clouds and nebulae. Clouds are studied in the nephology or cloud physics branch of meteorology.
On Earth the condensing substance is typically water vapor, which forms small droplets or ice crystals, typically 0.01 mm in diameter. When surrounded by billions of other droplets or crystals they become visible as clouds. Dense deep clouds exhibit a high reflectance (70% to 95%) throughout the visible range of wavelengths. They thus appear white, at least from the top. Cloud droplets tend to scatter light efficiently, so that the intensity of the solar radiation decreases with depth into the gases, hence the gray or even sometimes dark appearance at the base. Thin clouds may appear to have acquired the color of their environment or background and clouds illuminated by non-white light, such as during sunrise or sunset, may appear colored accordingly. In the near-infrared range, clouds look darker because the water that constitutes the cloud droplets strongly absorbs solar radiation at those wavelengths.
This text uses material from Wikipedia, licensed under CC BY-SA